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<FONT color="green">001</FONT>    <a name="line.1"></a>
<FONT color="green">002</FONT>    /*<a name="line.2"></a>
<FONT color="green">003</FONT>     * Copyright (C) 2009 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<FONT color="green">004</FONT>     *<a name="line.4"></a>
<FONT color="green">005</FONT>     * $Id: UTF8.html 2 2009-12-17 02:39:56Z archie.cobbs $<a name="line.5"></a>
<FONT color="green">006</FONT>     */<a name="line.6"></a>
<FONT color="green">007</FONT>    <a name="line.7"></a>
<FONT color="green">008</FONT>    package org.dellroad.lzma.client;<a name="line.8"></a>
<FONT color="green">009</FONT>    <a name="line.9"></a>
<FONT color="green">010</FONT>    /**<a name="line.10"></a>
<FONT color="green">011</FONT>     * Encodes and decodes strings to/from binary using "modified UTF-8 encoding".<a name="line.11"></a>
<FONT color="green">012</FONT>     * This is the same encoding as is used by Java class files.<a name="line.12"></a>
<FONT color="green">013</FONT>     */<a name="line.13"></a>
<FONT color="green">014</FONT>    public final class UTF8 {<a name="line.14"></a>
<FONT color="green">015</FONT>    <a name="line.15"></a>
<FONT color="green">016</FONT>        private UTF8() {<a name="line.16"></a>
<FONT color="green">017</FONT>        }<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>        /**<a name="line.19"></a>
<FONT color="green">020</FONT>         * Encode the given string.<a name="line.20"></a>
<FONT color="green">021</FONT>         */<a name="line.21"></a>
<FONT color="green">022</FONT>        public static byte[] encode(String s) {<a name="line.22"></a>
<FONT color="green">023</FONT>            final char[] chars = s.toCharArray();<a name="line.23"></a>
<FONT color="green">024</FONT>            int elen;<a name="line.24"></a>
<FONT color="green">025</FONT>    <a name="line.25"></a>
<FONT color="green">026</FONT>            // Compute encoded length<a name="line.26"></a>
<FONT color="green">027</FONT>            elen = 0;<a name="line.27"></a>
<FONT color="green">028</FONT>            for (int i = 0; i &lt; s.length(); i++) {<a name="line.28"></a>
<FONT color="green">029</FONT>                int ch = chars[i];<a name="line.29"></a>
<FONT color="green">030</FONT>                if (ch &gt;= 0x0001 &amp;&amp; ch &lt;= 0x007f)<a name="line.30"></a>
<FONT color="green">031</FONT>                    elen++;<a name="line.31"></a>
<FONT color="green">032</FONT>                else if (ch == 0x0000 || (ch &gt;= 0x0080 &amp;&amp; ch &lt;= 0x07ff))<a name="line.32"></a>
<FONT color="green">033</FONT>                    elen += 2;<a name="line.33"></a>
<FONT color="green">034</FONT>                else<a name="line.34"></a>
<FONT color="green">035</FONT>                    elen += 3;<a name="line.35"></a>
<FONT color="green">036</FONT>            }<a name="line.36"></a>
<FONT color="green">037</FONT>    <a name="line.37"></a>
<FONT color="green">038</FONT>            // Do the actual encoding<a name="line.38"></a>
<FONT color="green">039</FONT>            byte[] data = new byte[elen];<a name="line.39"></a>
<FONT color="green">040</FONT>            elen = 0;<a name="line.40"></a>
<FONT color="green">041</FONT>            for (int i = 0; i &lt; s.length(); i++) {<a name="line.41"></a>
<FONT color="green">042</FONT>                int ch = chars[i];<a name="line.42"></a>
<FONT color="green">043</FONT>                if (ch &gt;= 0x0001 &amp;&amp; ch &lt;= 0x007f)<a name="line.43"></a>
<FONT color="green">044</FONT>                    data[elen++] = (byte)ch;<a name="line.44"></a>
<FONT color="green">045</FONT>                else if (ch == 0x0000<a name="line.45"></a>
<FONT color="green">046</FONT>                    || (ch &gt;= 0x0080 &amp;&amp; ch &lt;= 0x07ff)) {<a name="line.46"></a>
<FONT color="green">047</FONT>                    data[elen++]<a name="line.47"></a>
<FONT color="green">048</FONT>                        = (byte)(0xc0 | ((ch &gt;&gt; 6) &amp; 0x1f));<a name="line.48"></a>
<FONT color="green">049</FONT>                    data[elen++] = (byte)(0x80 | (ch &amp; 0x3f));<a name="line.49"></a>
<FONT color="green">050</FONT>                } else {<a name="line.50"></a>
<FONT color="green">051</FONT>                    data[elen++]<a name="line.51"></a>
<FONT color="green">052</FONT>                        = (byte)(0xe0 | ((ch &gt;&gt; 12) &amp; 0x0f));<a name="line.52"></a>
<FONT color="green">053</FONT>                    data[elen++]<a name="line.53"></a>
<FONT color="green">054</FONT>                        = (byte)(0x80 | ((ch &gt;&gt; 6) &amp; 0x3f));<a name="line.54"></a>
<FONT color="green">055</FONT>                    data[elen++] = (byte)(0x80 | (ch &amp; 0x3f));<a name="line.55"></a>
<FONT color="green">056</FONT>                }<a name="line.56"></a>
<FONT color="green">057</FONT>            }<a name="line.57"></a>
<FONT color="green">058</FONT>            return data;<a name="line.58"></a>
<FONT color="green">059</FONT>        }<a name="line.59"></a>
<FONT color="green">060</FONT>    <a name="line.60"></a>
<FONT color="green">061</FONT>        /**<a name="line.61"></a>
<FONT color="green">062</FONT>         * Decode the given UTF-8 data.<a name="line.62"></a>
<FONT color="green">063</FONT>         *<a name="line.63"></a>
<FONT color="green">064</FONT>         * @throws IllegalArgumentException if the UTF-8 input is invalid<a name="line.64"></a>
<FONT color="green">065</FONT>         */<a name="line.65"></a>
<FONT color="green">066</FONT>        public static String decode(byte[] utf) {<a name="line.66"></a>
<FONT color="green">067</FONT>            StringBuilder buf = new StringBuilder(utf.length);<a name="line.67"></a>
<FONT color="green">068</FONT>            for (int i = 0; i &lt; utf.length; i++) {<a name="line.68"></a>
<FONT color="green">069</FONT>                int x = utf[i] &amp; 0xff;<a name="line.69"></a>
<FONT color="green">070</FONT>                if ((x &amp; 0x80) == 0) {<a name="line.70"></a>
<FONT color="green">071</FONT>                    if (x == 0)<a name="line.71"></a>
<FONT color="green">072</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.72"></a>
<FONT color="green">073</FONT>                    buf.append((char)x);<a name="line.73"></a>
<FONT color="green">074</FONT>                } else if ((x &amp; 0xe0) == 0xc0) {<a name="line.74"></a>
<FONT color="green">075</FONT>                    if (i + 1 &gt;= utf.length)<a name="line.75"></a>
<FONT color="green">076</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.76"></a>
<FONT color="green">077</FONT>                    int y = utf[++i] &amp; 0xff;<a name="line.77"></a>
<FONT color="green">078</FONT>                    if ((y &amp; 0xc0) != 0x80)<a name="line.78"></a>
<FONT color="green">079</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.79"></a>
<FONT color="green">080</FONT>                    buf.append((char)((x &amp; 0x1f) &lt;&lt; 6) | (y &amp; 0x3f));<a name="line.80"></a>
<FONT color="green">081</FONT>                } else if ((x &amp; 0xf0) == 0xe0) {<a name="line.81"></a>
<FONT color="green">082</FONT>                    if (i + 2 &gt;= utf.length)<a name="line.82"></a>
<FONT color="green">083</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.83"></a>
<FONT color="green">084</FONT>                    int y = utf[++i] &amp; 0xff;<a name="line.84"></a>
<FONT color="green">085</FONT>                    if ((y &amp; 0xc0) != 0x80)<a name="line.85"></a>
<FONT color="green">086</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.86"></a>
<FONT color="green">087</FONT>                    int z = utf[++i] &amp; 0xff;<a name="line.87"></a>
<FONT color="green">088</FONT>                    if ((z &amp; 0xc0) != 0x80)<a name="line.88"></a>
<FONT color="green">089</FONT>                        throw new IllegalArgumentException("invalid UTF-8");<a name="line.89"></a>
<FONT color="green">090</FONT>                    buf.append((char)(((x &amp; 0x0f) &lt;&lt; 12) | ((y &amp; 0x3f) &lt;&lt; 6) | (z &amp; 0x3f)));<a name="line.90"></a>
<FONT color="green">091</FONT>                } else<a name="line.91"></a>
<FONT color="green">092</FONT>                    throw new IllegalArgumentException("invalid UTF-8");<a name="line.92"></a>
<FONT color="green">093</FONT>            }<a name="line.93"></a>
<FONT color="green">094</FONT>            return buf.toString();<a name="line.94"></a>
<FONT color="green">095</FONT>        }<a name="line.95"></a>
<FONT color="green">096</FONT>    }<a name="line.96"></a>
<FONT color="green">097</FONT>    <a name="line.97"></a>




























































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